(pack) Piston-Rod Sealing U-ring K21 PU ID 42mm-48mm (choose dimensions)

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(pack) Piston-Rod Sealing U-ring K21 PU ID 42mm-48mm (choose dimensions) :
$1.92

Welcome to our oil seal store. Huge amount of differentdimensions and materials are on stock!! Don´t hasitate to contact us. We alsohave o-ring store, bearing store,chain store,

hydraulic and pneumatic seals store, belt store, etc - wecan send together. Most of oil sealsare on stock, so we are usually shipping within 2 bussiness days.

Longer handling time 10-20 days occures just on sold outitems.

We can also use UPSexpress shipping. Shipping rates are: UPS to USA 30USD,UPS to Europe, U.K, Germany, France20USD,

UPS to N.a S.America, Canada, Mexico, Brazil, Asia, China,Japan, Australia 50USD

K21 is a single acting piston - rod seal and designed tohave symmetrical lips in order to be used both for rod and piston applications.

PRODUCT ADVANTAGES

• Superior static and dynamic sealing effect

• Wide range of dimensions

• Easy assembly into closed grooves

• Simple groove design

• Economical sealing solution

APPLICATION

Construction machinery , fork-lift trucks , injectionmoulding machines , agricultural machinery , loading platforms and standardcylinders.

MATERIAL CODE

NBR 90 SHORE A NB9001

PU 92 SHORE A PU9201

OPERATING CONDITIONS

NBR

MEDIA Mineral oils(DIN51524) HFA and HFB HFC

TEMPERATURE -30°C+105°C +5°C +60°C -30°C +60°C

PRESSURE ≤150Bar ≤150 Bar ≤150 Bar

SPEED ≤0.5 m/sn ≤0.5 m/sn ≤0.5 m/sn

MEDIA Mineral oils(DIN51524) HFA and HFB HFC

TEMPERATURE -30°C+100°C +5°C +50°C -30°C +40°C

PRESSURE ≤400Bar ≤400 Bar ≤400 Bar

SPEED ≤0.5 m/sn ≤0.5 m/sn ≤0.5 m/sn

Note: The above data are maximum values and cannot be usedat the same time.

SURFACE ROUGHNESS Ra Rmax

Sliding Surface ØD-Ød ≤0.4μm ≤3.2 μm

Groove Base ØDb-Ødp ≤1.6μm ≤10 μm

Groove Flanks B ≤3.2μm ≤16 μm

Note: It is recommended to have 50% to 90% of the workingsurface material contact area value.

INSTALLATION

Easily assembled into closed grooves according to theminimum diameter values that are given in the below table. Open grooves orspecial assembly tools should be used for the values that are outside thistable. It is very important that the assembly tools must be of soft materialand have no sharp edges. Before installation the wiper must be oiled withsystem oil.

MINUMUM DIAMETER VALUES FOR CLOSED TYPE OF GROOVES

(D-d)/2 (mm) 4 5 6 7.7 10 12.5 15

dmin (mm) 25 30 40 50 80 100 105

NOTES For special applications that require hightemperatures , K21 can be produced in FKM material. The permissible sealing gapvalues of K21 piston -rod seal is given in the below table.

PERMISSIBLE SEALING GAP

NBR Smax (mm)

t=(D-d)/2 50Bar 100 Bar 150 Bar

t≤5 0.40 0.20 0.10

t>5 0.45 0.25 0.15

PU Smax (mm)

t=(D-d)/2 150Bar 250 Bar 400 Bar

t≤5 0.30 0.20 0.15

t>5 0.35 0.25 0.20

Note: The largest sealing gap value occurring on thenon-pressurized side of the seal does have a vital importance for the functionof the seal and in this respect it is quite important to use the S value lowerthan the above indicated numbers.